There are zillions of mail servers out there.
If you are an email publication publisher, you have no idea who is using AOL, who is using EarthLink, or MSN, etc.
How can you make sure that your mailing won’t be chucked away as worthless spam?
Here is a solution:
This web site can generate whitelisting instructions for an amazing variety of mail servers.
Just fill in the blanks and click the button and BINGO! It generates an HTML copy that you can post to your page and then direct your recipients to check it out to see what they can do to whitelist your emails, regardless of what mail server they use.